如何更改列表中项目的格式？

Question

我尝试使用谷歌图表，谷歌图表中的数据格式像[新日期(2015，1，1)，5]，[新日期(2015，1，2)，7]，[新日期(2015，1，3)，3]

function drawChart() {

    var data = new google.visualization.DataTable();
    data.addColumn('date', 'Time of Day');
    data.addColumn('number', 'Rating');

    data.addRows([
      [new Date(2015, 0, 1), 5],  [new Date(2015, 0, 2), 7],  [new Date(2015, 0, 3), 3],
      [new Date(2015, 0, 4), 1],  [new Date(2015, 0, 5), 3],  [new Date(2015, 0, 6), 4],
      [new Date(2015, 0, 7), 3],  [new Date(2015, 0, 8), 4],  [new Date(2015, 0, 9), 2],
      [new Date(2015, 0, 10), 5], [new Date(2015, 0, 11), 8], [new Date(2015, 0, 12), 6],
      [new Date(2015, 0, 13), 3], [new Date(2015, 0, 14), 3], [new Date(2015, 0, 15), 5],
      [new Date(2015, 0, 16), 7], [new Date(2015, 0, 17), 6], [new Date(2015, 0, 18), 6],
      [new Date(2015, 0, 19), 3], [new Date(2015, 0, 20), 1], [new Date(2015, 0, 21), 2],
      [new Date(2015, 0, 22), 4], [new Date(2015, 0, 23), 6], [new Date(2015, 0, 24), 5],
      [new Date(2015, 0, 25), 9], [new Date(2015, 0, 26), 4], [new Date(2015, 0, 27), 9],
      [new Date(2015, 0, 28), 8], [new Date(2015, 0, 29), 6], [new Date(2015, 0, 30), 4],
      [new Date(2015, 0, 31), 6], [new Date(2015, 1, 1), 7],  [new Date(2015, 1, 2), 9]
    ]);

x = ['1/4/2014', '2/4/2014','3/4/2014']
z = [100,200,300]

y=[]
for i in x:
    lastconnection = datetime.strptime(i,"%d/%m/%Y").strftime('%Y,%m,%d')
    y.append((lastconnection))
time = map(lambda x,y:(x,y),y,z)

打印时间输出为：

[('2014,04,01', 100), ('2014,04,02', 200), ('2014,04,03', 300)]

问题是我不知道如何添加'new Date()'，并将Date放入括号中不加引号。有什么想法吗？？提前谢谢！

Answer 1

1）以下是谷歌将接受的唯一日期字符串格式...

"Date(Year, Month, Day, Hours, Minutes, Seconds, Milliseconds)"

例如。

"Date(2017, 4, 3, 7, 31, 49, 0)"  // <-- 05/03/2017 07:31:49

注意：以上字符串的月份必须减一

"Date(2017, 4, 3)"  // <-- 05/03/2017 12:00:00

2）但是，只有在使用json构建DataTable时，google才接受这种格式

这意味着数据不能在一个简单的数组中...

[["Date(2017, 4, 3)", 100]]  // <-- will not work

并且必须按照以下方式格式化...

{
  "cols": [
    {"label": "x", "type": "date"},
    {"label": "z", "type": "number"},
  ],
  "rows": [
    {"c":[{"v": "Date(2017, 4, 3)"}, {"v": 100}]}
  ]
}

google.charts.load('current', {
  callback: function () {
    var formatDate = new google.visualization.DateFormat({
      pattern: 'MM/dd/yyyy hh:mm:ss'
    });

    var jsonStr = '{"cols": [{"label": "Date", "type": "date"}],"rows": [{"c":[{"v": "Date(2017, 4, 3)"}]}]}';

    var data = new google.visualization.DataTable(jsonStr);

    formatDate.format(data, 0);

    var container = document.getElementById('chart_div');
    var chart = new google.visualization.Table(container);
    chart.draw(data);
  },
  packages:['table']
});

<script src="https://www.gstatic.com/charts/loader.js"></script>
<div id="chart_div"></div>